OTTAWA - The Harper government seems to be having second thoughts about the wisdom of lumping major changes to dozens of statutes into one massive budget bill.

NDP House leader Nathan Cullen says his Conservative counterpart, Peter Van Loan, is considering a New Democrat proposal to split the 400-plus-page budget implementation bill into five separate pieces of legislation.

Cullen expects to hear back from Van Loan late Tuesday or early Wednesday.

On Monday, Van Loan categorically ruled out splitting up the bill, calling the NDP proposal "just another attempt to delay this important job-creating bill."

But by Tuesday, a spokesman for the minister was no longer so unequivocal when asked about Cullen's assertion that his proposal is under discussion.

Fraser Malcolm would say only that the government House leader is "constantly having discussions with opposition House leaders on all matters; we never discuss those in public."

He did not respond when asked if Van Loan is no longer ruling out dividing the bill.

The budget bill — which includes reforms to environmental regulations, fisheries management and immigration law, among other things — has been widely condemned by opposition parties, environmentalists and other advocacy groups.

They maintain the government is trying to sneak through major, contentious, changes to non-budgetary statutes by stuffing them in the budget bill, where they will receive little separate scrutiny.

"Sending a 400-page bill that covered 60 different statutes to a sub-committee of finance just didn't make any sense," NDP Leader Tom Mulcair told reporters Tuesday.

"The number one thing that we're elected to do is to hold the government to account and make that analysis on behalf of all Canadians and we plan to do our jobs correctly."

In the House of Commons, Mulcair twice asked Prime Minister Stephen Harper to accept the NDP proposal for splitting the bill. Harper did not answer either question directly.

"The government received a mandate to make jobs and growth and long-term prosperity its major emphasis," Harper said.

"The economic action plan was put before this Parliament in March and approved in principle in April. A first bill is now before Parliament which will be debated in a record amount of time.

"I would encourage all members of Parliament to focus on that work and move forward on the priority of Canadians."

Shortly afterward, however, Finance Minister Jim Flaherty emerged from the Commons and nixed the idea of splitting the bill.

"No, there's one budget bill in the spring and one in the fall. It's the same as every other year," Flaherty insisted.

Cullen was not discouraged.

"The prime minister today had an opportunity to say 'no' and he didn't," Cullen said in an interview.

As for Flaherty, Cullen said he's been dealing with Van Loan on the issue and the House leader has seemed receptive.

"I don't get the sense that they're just stringing us along. I think they are actually contemplating our offer."

If the government refuses to split the bill, Mulcair warned that the NDP has other "legal" and parliamentary tools at its disposal that it could use to hold up the massive bill until all its various parts have been adequately studied.

"We have a lot of options and we'll exercise them," he said, refusing to elaborate.

Liberal House leader Marc Garneau said there are parliamentary procedural tools that his party is also willing to use but no legal tools that he's aware of. The Liberals also favour splitting the bill.